Use non-strict microk8s on IS-hosted runners

Author: carlcsaposs-canonical

spread.yaml

@@ -102,8 +102,11 @@ backends:
             # (These packages are being built when installing poetry or integration test Python
             # dependencies)
             CONCIERGE_EXTRA_DEBS: pipx,pkg-config,rustup
-            # s390x only available on edge
-            CONCIERGE_MICROK8S_CHANNEL: 1.32-strict/edge
+            # s390x only available on edge risk of microk8s snap
+            # IS-hosted GitHub runners do not work with the strictly confined microk8s snap:
+            # https://github.com/canonical/microk8s/issues/5082
+            # https://chat.canonical.com/canonical/pl/i6yydsx5ifrepp56khq5fq5dke
+            CONCIERGE_MICROK8S_CHANNEL: latest/edge
           variants:
             - -juju29
 
@@ -130,7 +133,7 @@ prepare: |
     # Running on IS-hosted runner; configure microk8s to use Docker Hub mirror
     # Run before concierge prepare because of https://github.com/canonical/concierge/issues/75
 
-    snap install microk8s --channel "$CONCIERGE_MICROK8S_CHANNEL"
+    snap install microk8s --channel "$CONCIERGE_MICROK8S_CHANNEL" --classic
   
     # Wait for microk8s to populate iptables
     # https://chat.canonical.com/canonical/pl/jo5cg6wqjjrudqd5ybj6hhttee